Significance: Almost 30% of U.S. adults have pre-diabetes. Without weight loss and changes in physical activity and diet, more than 50% of them will eventually develop type 2 diabetes (T2DM), with its increased risk of cardiovascular disease and many other complications. The Diabetes Prevention Program (DPP) proved that lifestyle changes involving weight loss, increased physical activity and dietary changes can delay or prevent the onset of T2DM in pre-diabetics. However, intensive interventions like DPP are expensive (DPP: $1,399/person) and demanding of both patient and professional time. As a result, despite the critical need to prevent progression to T2DM, prevention programs have not been embodied in effective, low-cost, real-world interventions that can assist millions of pre-diabetics. Objectives: The overall goal of this fast-track proposal is to produce a commercializable product aimed at changing physical activity, diet and weight loss behaviors of pre-diabetics. The specific aims are to 1) Adapt an existing successful email/Internet wellness program to focus on prediabetics; 2) Conduct a randomized trial of effectiveness in changing weight, glucose and physical activity in pre-diabetics; 3) Provide data on cost and participation, for commercialization and future phase 3 trials. Methods: Alive is an email-delivered intervention to improve physical activity and diet, developed through an R01 to Kaiser Permanente. In a randomized controlled trial, Alive significantly improved all of its target behaviors. The latest version, through an SBIR grant, has added automated tailored print and phone counseling, social networking and a substantial emphasis on weight control. Alive will now be modified to focus on pre-diabetes and the behaviors required for its effective control. The modified program will be delivered over I year through 3 channels (email/internet, phone, print), and will use computerized algorithms to deliver highly individualized weekly goal-setting and motivational support. In the clinical trial, pre-diabetics will be identified through the Kaiser Permanente member database. At clinic visits at baseline, 3 and 12 months, weight and measures of glycemic control will be obtained. Subjects will be randomly assigned to the modified program, Alive-PD, or a control condition representing usual care of pre-diabetics. There is statistical power to detect a clinically meaningful difference between the two groups in weight loss and glycemic control (A1c). Effectiveness, proportion reached, participation and cost will be reported. Impact: A low-cost program such as this could reach thousands or millions of prediabetics with a behavior- change intervention, at a fraction of the cost of in-person or group approaches. If proven effective at improving weight loss and glycemic control in a randomized trial, it could become an important component of the standard of care for prediabetics as a stand-alone service, as a complement to pre-diabetes education classes, and as an important reinforcer of physician and nurse practitioner recommendations.